حلول التدريبات العملية ديناميكا لجسم واحد

تعمل ثلاث قوى على الجسم: قوة الاحتكاك الحركي (عكس حركة الجسم)، وقوة الجاذبية والقوة العمودية.

 نرسم مخطط القوى:

في الاتجاه العمودي للسطح الجسم في وضع اتّزان، نكتب معادلات الحركة في اتجاه المحور :Y 

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في اتجاه نحو أسفل السطح المائل لا يكون الجسم في وضع اتّزان، بل يتحرك بتسارع. نكتب معادلات الحركة في اتجاه المحور:X 

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نعوض تعبير القوة العمودية من معادلة الحركة في اتجاه المحور Y في معادلة الحركة في اتجاه المحور X:

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نعبر عن التسارع:

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